Replacing A/C Compressor
Replacing A/C Compressor Hey guys - I need a bit of advice on changing my A/C compressor. Long story short, mine went out here in South Alabama (yes, VERY hot here), and I took it to the local A/C shop who found the compressor leaking and wanted to change it for over $900. They're a very good shop, highly recommended, but I just can't come up with that kind of cash for something I can *probably* do myself. Now, I'm fairly mechanically inclined and have the tools, so the actual install shouldn't be a problem. I'm going to change the accumulator/dryer at the same time as well. I'll take it just about anywhere to get the vacuum pulled on it and charged - that's not a problem. Here is what I need to know:
1) I know I need to have the system flushed...when do I do that? I'm assuming when the old compressor is off and the system is open?? Do I do that with the new or old dryer/accumulator?
2) Are there any seals/gaskets/o-rings that I should know about or have to buy separately? I'd hate to miss one of those and *** up the whole job.
Any and all advice/lessons learned would be greatly appreciated!
1) I know I need to have the system flushed...when do I do that? I'm assuming when the old compressor is off and the system is open?? Do I do that with the new or old dryer/accumulator?
2) Are there any seals/gaskets/o-rings that I should know about or have to buy separately? I'd hate to miss one of those and *** up the whole job.
Any and all advice/lessons learned would be greatly appreciated!
I replaced mine with a used unit.
I bought a new accumulator, it came with the necessary gaskets. I replaced the orifice tube. It sits in the liquid line (hard metal line below accumulator line) on the evaporator side. It did not come with a new gasket, so I reused the stock one. Same thing with the suction/discharge hose assy that connects to the compressor, no gaskets, so I reused. No problems.
I removed the compressor belt, unbolted the compressor (its hard to get to a couple of the bolts, but you can do it). With the compressor loose, I removed the suction/discharge hose assy.
I then took the new compressor and filled it with 4 ozs of PAG 150 oil. I poured the oil in the suction port and turned the compressor until the oil was sucked in. Then repeated until I had 4 ozs in the compressor. Bolt up the hose assy (yes you will spill some oil) and bolt the compressor back in, but leave the belt off. Replace orifice tube. Pour another 4 ozs of oil into the body of the accumulator. Bolt accumulator back in. Go back to the compressor and spin it a dozen times by hand to circulate the oil.
Have the system evacuated and recharged. Unless you have a clogged line or the compressor exploded, I don't think you need a flush.
I bought a new accumulator, it came with the necessary gaskets. I replaced the orifice tube. It sits in the liquid line (hard metal line below accumulator line) on the evaporator side. It did not come with a new gasket, so I reused the stock one. Same thing with the suction/discharge hose assy that connects to the compressor, no gaskets, so I reused. No problems.
I removed the compressor belt, unbolted the compressor (its hard to get to a couple of the bolts, but you can do it). With the compressor loose, I removed the suction/discharge hose assy.
I then took the new compressor and filled it with 4 ozs of PAG 150 oil. I poured the oil in the suction port and turned the compressor until the oil was sucked in. Then repeated until I had 4 ozs in the compressor. Bolt up the hose assy (yes you will spill some oil) and bolt the compressor back in, but leave the belt off. Replace orifice tube. Pour another 4 ozs of oil into the body of the accumulator. Bolt accumulator back in. Go back to the compressor and spin it a dozen times by hand to circulate the oil.
Have the system evacuated and recharged. Unless you have a clogged line or the compressor exploded, I don't think you need a flush.
Is replacing the accumulator nescessary? Or just something that you chose to do? Is the PAG oil nescessary since its a used compressor? I've seen guys selling compressors with very low miles for like 100ish shipped. I don't mind getting greasy, just wondering.
If I can use my current accumulator should I add more oil to it?
Also good to know I can have it evacuated just before I recharge. Thanks for all your help.
If I can use my current accumulator should I add more oil to it?
Also good to know I can have it evacuated just before I recharge. Thanks for all your help.
TECH Fanatic
Joined: Apr 2005
Posts: 1,231
Likes: 1
From: Just This Side of Damnation
From what I learned when I did mine:
-Each item replaced requires one oz. of replacement oil.
-The accumulator/dryer should be replaced if the system is left open for any period of time over a few hours.
-Be careful straining any other lines while you're replacing the compressor. I had to replace the high pressure line the following year, possibly leaking due to stress & strain.
-The compressor is a heavy bitch, but it isn't all that difficult. About a 5 on the 1-10 PITA scale.
-If you didn't have a catastrophic compressor failure that left little bits & chunks in the system you shouldn't HAVE to have a flush. A proper flush consists of doing each part of the system separately and will be expensive if done by a shop.
-I had a shop vacuum & refill the system after I did all the replacement work. $140-ish.
-If you're using a used compressor (I got a rebuilt one at a parts store) you should need to add more than an oz or so, just to be sure. Alternately, you could remove all the old oil and add what's recommended for a used compressor (but I don't know what that is.
-If you reuse your dryer you shouldn't need to add any oil to it.
-There is a LOT of information on the web and it's a good thing to seek it out.
-Much instruction came on the sheet I got with my rebuilt compressor.
-Each item replaced requires one oz. of replacement oil.
-The accumulator/dryer should be replaced if the system is left open for any period of time over a few hours.
-Be careful straining any other lines while you're replacing the compressor. I had to replace the high pressure line the following year, possibly leaking due to stress & strain.
-The compressor is a heavy bitch, but it isn't all that difficult. About a 5 on the 1-10 PITA scale.
-If you didn't have a catastrophic compressor failure that left little bits & chunks in the system you shouldn't HAVE to have a flush. A proper flush consists of doing each part of the system separately and will be expensive if done by a shop.
-I had a shop vacuum & refill the system after I did all the replacement work. $140-ish.
-If you're using a used compressor (I got a rebuilt one at a parts store) you should need to add more than an oz or so, just to be sure. Alternately, you could remove all the old oil and add what's recommended for a used compressor (but I don't know what that is.
-If you reuse your dryer you shouldn't need to add any oil to it.
-There is a LOT of information on the web and it's a good thing to seek it out.
-Much instruction came on the sheet I got with my rebuilt compressor.
The LS1 FBody A/C system holds 9ozs of PAG 150 oil. The majority of that sits in the compressor and the accumulator. Oreilly's sells it in 8 oz cans. I 'flushed' the old oil out of the used compressor before installation using the method above. I then poured the rest of the can into the accumulator. The compressor will circulate the oil, but when the system is not is use, the oil will reside in the accumulator and the compressor.
What I am saying is if your car's A/C hasn't worked for months, and you replace the compressor and the accumulator you are losing almost all of your oil. You need well more than 1 oz in each of those components.
I looked at buying a compressor on the board but every genius thinks their 100K mile POS compressor is worth 100 bucks. I bought mine at a local scrap yard for under 100 and it comes with a warranty.
What I am saying is if your car's A/C hasn't worked for months, and you replace the compressor and the accumulator you are losing almost all of your oil. You need well more than 1 oz in each of those components.
I looked at buying a compressor on the board but every genius thinks their 100K mile POS compressor is worth 100 bucks. I bought mine at a local scrap yard for under 100 and it comes with a warranty.
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Staging Lane
Joined: Mar 2006
Posts: 57
Likes: 0
From: Oklahoma City
The paperwork that came with the remanufactured compressor I bought said that my warranty on it would be void if I didn't replace the accumulator, and the HVAC guys at work said it is a really bad idea not to replace it. I got an accumulator from autoaironline.com for $48 it was the cheapest i found. I flushed my system myself. You can buy flush from autozone for $14, you isolate each line and component and flush it. I just poured some of the solvent into the condensor, evaporator and the lines. Then I blew the solvent out with 100 psi compressed air, it was simple. changing the compressor is easy, and so is the orifice tube which you must replace. If I were you i would change the compressor oil and refill with about 11 oz of PAG oil, 9 in the compessor and 2 in the accumulator. You also have to pull a vacuum on the system to check for leaks and remove all moisture. If you are able to find a shop that will just vacuum your system, you can refill it yourself with the 134a and hose kit that you can buy at any autoparts store, it will be cheaper. Put the UV dye in also, I just repaired mine about a month ago and it is ICE cold. Replace the accumulator.
Originally Posted by 00silverT/AWS6
If I were you i would change the compressor oil and refill with about 11 oz of PAG oil, 9 in the compessor and 2 in the accumulator.
Staging Lane
Joined: Mar 2006
Posts: 57
Likes: 0
From: Oklahoma City
The New Orifice tube I bought had a slip of paper that said to add 2 oz of additional oil to the system when you are replacing the orifice tube. I told him to change the compressor oil so he would have to add 9 oz back to the compressor after he drains 9 oz.
yeah guys but the accumulator is the bottle under the hood correct?but my ac went out on me as well but i got metal in the orfice tube so i need to replace the evaporator which they told me u have to remove the whole dash?and that is a bitch.is there any easier way?
